The Glo-Bob Running Shirt consists of a terry cloth inner lining that absorbs sweat while you run and keeps you cool as you heat up. Most runners report that while running on a hot day, the Glo-Bob Running Shirt actually makes them feel cooler when compared to running without a shirt. Sweat in your eyes? Not a problem. The Glo-Bob Running Shirt has a hidden inner pocket large enough to safely carry a key, money or credit card, and the design allows you to wipe for face easily, without breaking stride. Try it for one race. We guarantee you'll love it.